spotting 6dpo

so 6 dpo i had light brown spotting literally only had a small spot in my under wear, i took at test aroubd 12 dpo (2 days before my expected period) it was neg. my period is now a day late ive been nauseous for a week with headaches on and off. could i still be pregnant or is this not my month. I'm nervous to test again because i had a chemical pregnancy around 8 months ago after trying for over a year.